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Discussion Starter · #1 · (Edited)
Has anyone used the YST threadless square taper bottom bracket?It is designed to be used when the BB shell has damaged or absent threads.Does the the BB shell have to be precision chamfered to accept the cups or will a friction fit work?No instructions are provided with the BB.Thanks for any replies.
 

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I've never had a frame without bb shell threading, nor have I damaged one bad enough to need to think about a pressed in bb (and would probably look to bmx style off the top of my head). What are the other details of this system? Does it have more than one spindle length or has adjustability or what? Which type of square spindle does it work with? Could be handy for an old beater someday...
 

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zephyr said:
Has anyone used the YST threadless square taper bottom bracket?It is designed to be used when the BB shell has damaged or absent threads.Does the the BB shell have to be precision chamfered to accept the cups or will a friction fit work?No instructions are provided with the BB.Thanks for any replies.
The Mavic BB needed the shell to be chamfered. It was the only BB of this type I knew of.

Are the lockrings of the YST tapered? If not I would just face the shell
 

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Discussion Starter · #4 ·
The YST threadless BB is JIS square taper and comes in 110,113,119,122 and 124mm spindle lengths.It looks like it is designed to grab the edge of the BB shell and hold it by friction-one cup is threaded to the shell of the BB itself to tighten using a standard Shimano cartridge BB tool.I know that the Mavic BB requires chamfering with a special expensive and rare shop tool ,but I have never seen one of the Mavic BBs.The frame I intend to use it on is aluminum and left the factory [by mistake]with no threading, and that I ended up with for free after getting a properly threaded replacement for the frame.I want to salvage the frame using one of the YSTs and thus I am seeking reports from those who have installed and used one.
 

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Why not find a shop with the Campy BB tools that would be willing to tap the shell? I would not want to try it on a steel frame but it should not be that big a deal with aluminum.
 

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Discussion Starter · #6 · (Edited)
Threading the bare BB shell would be an option if it was not too expensive or problematic at the bikeshop level.I would guess a machine shop or framebuilder could do it,but at a high cost.A good idea to explore.The YST BB was only $15.
 
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